While the TSB report isn’t expected until 2013, the director of its air investigations branch has already issued two safety warnings.

These suggest changes to procedures and regulations intended to improve air transportation safety.

First Air Flight 6560 risked a near miss with another aircraft, says a letter that Mark Clitsome, director of the TSB’s air investigations branch, wrote this past Feb. 8 to Major-General J.A.J. Parent at the Canadian Air Division headquarters in Winnipeg.

“Had the First Air flight not hit the ground there could have been a risk of a mid-air collision,” Clitsome said in the letter, which details procedural gaps that affected the safety of the airport air traffic on Aug. 20, 2011.

The letter relates how on that day, the Boeing 737-210C was flying from Yellowknife to Resolute Bay, when at 11:42 a.m., during its approach to Runway 35T, the jet collided with a hill about one nautical mile east of the airport, killing 12 people and injuring three.

That took place during the Operation Nanook military sovereignty exercise, when the Canadian Forces had set up a temporary “Class D” control zone in Resolute Bay to handle increased air traffic and provide training within its air traffic management program.

At 11:39 a.m. a second aircraft operating under instrument flight rules entered the control zone without “appropriate” separation, Clitsome noted.

When in Class D air space, aircraft must be equipped with radios able to communicate with air traffic control, receive permission to enter the airspace and not fly too close to any other aircraft in the same airspace.

The letter notes that the military radar equipment brought there for Operation Nanook was not ”useable at the time of the accident as a flight check had not been performed to verify radar accuracy.”

The military air controllers didn’t have all procedures in place and the “separation standards” were not applied, Clitsome said.

The operation in Resolute Bay was to be the first “complete airfield operation in a civil environment,” he said.

But it didn’t have a contingency plan to provide instrument flight rules services “in a non-radar environment” and if these weren’t provided, the results could be “catastrophic.”

If future such operations don’t include a provision for all the air traffic services required, “this risk will persist,” Clitsome said.

A second letter from Clitsome sent in April to Martin Eley, Transport Canada’s director general of civil aviation, noted that the in-flight data recorder on board the First Air jet contained “invalid data” for the first 29 minutes of the flight.

“Had the accident occurred during this period, data vital to the investigation would be missing,” Clitsome said.

The problems with the data recorder, which were found later, couldn’t be detected with the current review standards, so there may be “unserviceable” flight data recording systems installed on operating transport aircraft, he suggested.

Clitsome, who also suggested the current standards provide “insufficent data,” said he was providing that information for appropriate “follow-up actions.”

The TSB progress report notes that when the crew initiated the go-around just before impact, the aircraft’s landing gear was down and locked, the plane’s speed was 157 knots and the final landing checklist was complete.

The final TSB report will look at the causes and contributing factors that led the crash, but its purpose is not to assign fault.